Radeon re-assigns disk letter

I have an HP Envy laptop which notified me that I should update the Radeon driver, which I did. It is now Radeon Software version 19.10.02.13.

However, I have an SD card drive that I assigned letter S. When I re-booted it was re-assigned to Drive D. I tried running Disk Management to assign it back to S. It allows me to do it, but gives a message "The volume in Disk 2 (D) Simple Volume is currently in use. If you continue the new drive letter will be assigned, but you can still use the old drive letter to access the volume until you restart the computer. The old drive letter will not be available for assignment until you restart.". Windows Explorer then shows the drive as S, but when I restart it reverts back to D.

I don't have any other apps running, so I think the only program that is using the drive (and apparently blocking Disk Manager) is Radeon. I have tried closing any apps I don't recognise through Resource Monitor, but whatever I do I can't re-assign the drive.

I have proved conclusively that this problem is due to AMD Radeon. I tried numerous ways of assigning drive letter S: to my SD card, using Disk Manager, Powershell and editing the registry through Regedit. In every case I was able to assign the required letter, but when I rebooted it reverted back to drive D:. I then uninstalled AMD Radeon and voila! the drive letter remained at S:.

I suspect that Radeon installs during reboot before Windows searches for drives. Windows then thinks a new SD card has been inserted and assigns a letter to it, rather than recognising that it was an existing drive.

Well you have proven it is the AMD driver therefore I suggest you open an Online AMD Service Request (Official AMD SUPPORT) and let them know and see what they suggest you do to fix or have a work around from here: https://www.amd.com/en/support/contact-email-form